Hi
using a DrDaq to log voltage data but when setting up the system we get noise on the signal that cannot be removed.
if we try shorting the input connectors i would expect to see zero volts but the noise moves from 0 to 30mv
the signal we are measuring is in the range zero to 0.5 v
any solutions or do we have a faulty Dr Daq
Hi data recording uploaded as file atachment
Test run with noise
voltage input is on the top line and had the input leads shorted together, when using it with the measuring source we get the same level of noise that interferes with the signal we are trying to look at.
But which range of the four for the DrDaq are you using
±1.25 V, ±2.5 V, ±5 V, ±10 V
As the scope is 8 bits you have 255 steps across the specified range, so if you are on the 10V scale this would give a step resolution of 78mV, on the 1.25V range you would get 10mV.
The noise looks to be within the ±3% accuracy quoted for the oscilloscope channel of the DrDaq. As this is gaussian noise it can be removed by using a software moving average filter, resolution enhancement in Picoscope software.
Hi
Thanks
looks like a soulution for now, possibly plot the average reading over 10 - 20 samples to smooth out the curve but problen is that i am looking for small transiant changes in the force.
i will keep experimenting see if i can get any better results
possibly have to resort to a more expensive 24 bit model of A to D